spring CRUD DELETE action that return viewmodel or empty body

Question

I want to write a DELETE action that return a no content body if no id error exist. If id not exist I want to redirect to the coresponding GET view.

Controller code:

@RequestMapping(value = "/todo/delete/{id}", method = RequestMethod.GET)
public String getDeleteTodo(Model model, @PathVariable("id") String id)
{
    Optional<Todo> todo = todoRepository.findById(Long.decode(id));

    if (todo.isEmpty()) {
        model.addAttribute("msginfo", "ctl-todo.delete.msginfo.id-not-exist");
        model.addAttribute("requestedId", id);
    }
    else {
        model.addAttribute("todo", todo.get());
    }

    return "v-todo-delete";
}

@RequestMapping(value = "/todo/delete/{id}", method = RequestMethod.DELETE)
public String deleteTodo(@PathVariable String id, RedirectAttributes redirAttrs)
{
    boolean exists = todoRepository.existsById(Long.decode(id));

    if (exists) {
        todoRepository.deleteById(Long.decode(id));
        return ""; //here I want to return a no-content body response
    }
    else {
        redirAttrs.addFlashAttribute("msginfo", "ctl-todo.delete.msginfo.id-not-exist");
        redirAttrs.addFlashAttribute("requestedId", id);

        return "redirect:/todo/delete" + id;
    }
}

More informations about the view:

The GET view is juste a view that display the todo entity corresponding to the id. The deletion is make with a button using ajax to call the DELETE method. Then response is return as 204 with no content into the body, i redirect the user with javascript to the main page... If an id not exist in the DELETE method, I want to redirect to the GET method to show an error message.

If someone have an idea to do this. Thanks in advance.

Answer 1

Final anwser for me:

@RequestMapping(value = "/todo/delete/{id}", method = RequestMethod.DELETE)
public ResponseEntity<?> deleteTodo(@PathVariable String id, RedirectAttributes redirAttrs)
{
   boolean exists = todoRepository.existsById(Long.decode(id));

   if (exists) {
       todoRepository.deleteById(Long.decode(id));
       return new ResponseEntity<>(HttpStatus.NO_CONTENT);
   }
   else {
       redirAttrs.addFlashAttribute("msginfo", "ctl-todo.delete.msginfo.id-not-exist");
       redirAttrs.addFlashAttribute("requestedId", id);
       /* I use CONFLICT here to explain that the entity was possibly deleted
          by another user between the moment the user give the view containing
          the DELETE ajax link and the moment he click on it. */
       return new ResponseEntity<String>( "redirect:/todo/delete" + id, HttpStatus.CONFLICT);
   }
}

Thank you Mandar Dharurkar & Jeethesh Kotian for your help ;)